Background Information

Definitions

Acne: blockage and inflammation of the pilosebaceous unit (hair follicle + hair shaft + sebaceous gland)

2 main presentations:

• Comedones: non-inflamed follicular plugs
• Papules and pustules: inflammatory acne lesions

Causes and Risk Factors

Processes involved in pathogenesis:

• Proliferation of Cutibacterium acnes
• Androgen-induced seborrhoea
• Altered follicular keratinocyte proliferation

Main risk factors:

• Family history
• Increased androgen activity
  • Puberty
  • Polycystic ovarian syndrome
  • Other conditions associated with hyperandrogenism

Clinical Features

Affected site:

• Face (99%)
• Back (60%)
• Chest (15%)

Clinical features:

• Comedones
  • Open comedones (blackheads): dark open portion of sebaceous material
  • Closed comedones (white heads): closed small round lesions with white material (sebum and shed keratin)

 

• Inflammatory acne: occurs when follicle bursts and releases irritants, red +/- painful
  • Papular / pustular acne: <5mm, arise from comedones
  • Nodulocystic acne: >5mm commonly affects neck and back
  • Acne conglobata: severe form of nodulocystic acne with interconnecting sinuses and abscesses
  • Acne fulminans: rare severe form characterised by painful ulcerative skin lesions and systemic upset

 

• Seborrhoea – common
• Scarring
• Pigmentation

Acne Severity Scale

2 main severities outlined by NICE:

Severity	Criteria (≥1 features)
Mild to moderate	Any number of comedones <35 inflammatory lesions <3 nodules
Moderate to severe	≥35 inflammatory lesions ≥3 nodules

Management

Referral Criteria

Refer to secondary care if any of the following:

• Acne fulminans – same day referral
• Acne conglobata
• Nodulo-cystic acne
• Uncertain diagnosis

Consider referral if any of the following:

• Mild to moderate acne not responded to 2 courses of treatment
• Moderate to severe acne not responded to oral antibiotics
• Acne with scarring
• Acne associated with psychological distress / mental health disorder
• Acne with persistent pigmentary changes

Conservative Management

Offer skin care advice:

• Non-alkaline (pH neutral / slightly acidic) synthetic detergent cleansing product BD
• Remove makeup at the end of the day
• Avoid oil-based and comedogenic skin care products and sunscreens
• Avoid picking and scratching acne lesions (↑ risk of scarring)

Pharmacological Management

DONT’s and Contraindications in Acne Management

NICE states explicitly NOT to offer:

• Antibiotic monotherapy (topical / oral)
• Combination of topical and oral antibiotics (if an antibiotic is given, the other drug should be a NON-antibiotic)

These options increase risk of antibiotic resistance + antibiotics (oral or topical) work best with other topical agents (e.g., benzoyl peroxide).

Pregnancy contraindications:

• Any form of retinoids (topical / oral)
• Tetracyclines

Medications safe for pregnancy:

• Erythromycin
• Topical clindamycin
• Topical benzoyl peroxide

1st Line Therapy

Offer 12-week course of dual therapy from a choice of the following:

Severity	Choice of Therapy
Any	Fixed combination topical adapalene + topical benzoyl peroxide  Fixed combination topical tretinoin + topical clindamycin **Adapalene and tretinoin are retinoids
Mild to moderate	Combined topical therapy are 1st line: Options from 1st row, or Fixed combination topical benzoyl peroxide + topical clindamycin
Moderate to severe	Options from 1st row, or Options with oral antibiotics: Oral tetracycline (doxycycline / lymecycline) + fixed combination topical benzoyl peroxide + topical adapalene  Oral tetracycline (doxycycline / lymecycline) + topical azelaic acid **Alternative to tetracycline: trimethoprim / macrolide

NICE also recommends considering COCP + topical agents as an alternative to systemic antibiotics in women

2nd Line Therapy

Topical benzoyl peroxide monotherapy

3rd Line Therapy / Secondary Care Interventions

Oral Isotretinoin

Standard dose: 0.5-1 mg/kg until total cumulative dose of 120-150 mg/kg (but consider discontinuing sooner if adequate response and no acne lesions for 4-8 weeks)

• Only to be considered in >12 y/o with severe form of acne that is resistant to adequate courses of standard therapy with topical therapy and systemic antibiotics

Important safety information from MHRA:

• Teratogenic (exclude pregnancy + effective contraception 1 month before, during and for 1 month after discontinuation)
• Assess prior initiating and counsel patients about:
  • Mental health side effects
  • Sexual function side effects
• 2 independent prescribers need to agree on the initiation of isotretinoin in patients under 18 years

Other Treatment

• Photodynamic therapy 
• Intralesional triamcinolone acetonide (corticosteroid) for severe inflammatory cysts

Review and Follow-Up

Offer review 1st line therapy at 12 weeks.

If there is inadequate response to 12-week course of 1st line therapy:

• Mild to moderate: offer alternative option from above
• Moderate to severe:
  • No antibiotic used → offer option with oral antibiotic
  • Antibiotic used already → consider referral

Maintenance Therapy

Encourage appropriate skin care and consider maintenance therapy only in those with history of frequent relapse:

• 1st line: fixed combination topical benzoyl peroxide + topical adapalene
• 2nd line: monotherapy topical adapalene / azelaic acid / benzoyl peroxide

Acne-Related Scarring

If scarring persists 1 year after acne cleared → refer to specialist to consider:

• CO₂ laser treatment
• Glycolic acid peel

References